As far as I can remember, this is an 8052AH Basic board that has been published in Elektor somewhere in the 1980's. As you have noted, it can be used in combination with a standard terminal or terminal emulator program. The ZIF socket is there to allow EPROM's to be programmed as well (there's a switch to change the EPROM programming voltage).

If you would want to experiment with BASIC, you should first get hold of a datasheet of the 8052AH Basic controller (probably still around on the Internet, I guess).

I can probably get hold of the schematic diagram of this board if you want; just let me know and I'll send it to you in the course of the week. The documentation of the board has been published in several issues of Elektor; that I probably have as well, but it's in Dutch ...

However, if you are not interested in using BASIC at all, I would scrap the board if I were you. There are much better (and easier to use) alternatives around these days.